The best advice I can give you is that no matter what anyone says, you only need time to think.
Take as much time as possible to make thought out decisions.
Never promote bad behavior.
When you eventually realize what this means, maybe in your thirties, and you will be amazed of what you have achieved. You will also be aghast of how poorly people have tied to influence you.
I would stay away from alcohol and any type of medicine if possible. Also avoid processed foods, eating eggs and steak is not only cheap and nutritious, but healthy as can be.
Stay safe, and always find time to think.